1/4 converted into a decimal is .25
20÷.25=80
the answer is 80
Answer:
first one is right
Step-by-step explanation:
Answer:
x=179
Step-by-step explanation:
Answer:
Step-by-step explanation:
A) identical triangles PSR and PSQ
B) in the given triangle PQR angle P is 90 degrees and PS is perpendicular on QR. so the angle PSR and angle PSQ is 90 degrees also angles RPS , SPQ are 45 degrees . hence when two angles of a triangle are 90 and 45 degrees. the third is also 45 degrees. when the three angles of two triangles are equal they are said to be similar
C) the triangle PSR is a isosceles triangle therfore the two sides of the two oposite equal angles must be equal. if RS=4 then SP=4 as well the sides opposite to 45 degrees angles. the third side can be found by using the formula
c²=a²+b²
c²=4²+4²=16+16=32
c=√32=√16*2=4√2
Given:
Nana has a water purifier that filters 
of the contaminants each hour.
Water has contaminants = 
To find:
The function that gives the remaining amount of contaminants in kilograms, C(t), t hours after Nana started purifying the water.
Solution:
Let C(t) be the remaining amount of contaminants in kilograms after t hours.
Initial amount of contaminants =
Decreasing rate is .
Using the exponential decay model:
where, 
is initial amount of contaminants, r is the decreasing rate and t is time in hours.
Substituting the values, we get
Therefore, the required function is .
